Malicious PDF — malware analysis report

Static analysis result for SHA-256 f944ad366c4cdfb6…

MALICIOUS

PDF

88.4 KB Created: 2021-09-09 22:21:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 282878ab8c454b0c7cf7d0d0285b0f34 SHA-1: 91acdb86e0d3526e2ff3cad9ad8c57b2d4325b9c SHA-256: f944ad366c4cdfb6012153eab284a00dba15515fd8a0085e42681bed1529c618
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which are hosted on compromised websites or disposable domains, suggesting a link farm or phishing attempt. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://mariapolis.es/ckfinder/userfiles/files/garilevagokotinatetife.pdf In PDF document text
    • http://ventmetal.ru/userfiles/files/nepon.pdfIn PDF document text
    • http://altaprecision.com/userfiles/file/65662912841.pdfIn PDF document text
    • https://bitree.com/ckfinder/userfiles/files/87076993109.pdfIn PDF document text
    • https://elesud.it/img_pagine/file/laxiwasevatavedopolu.pdfIn PDF document text
    • https://ibeguiristain.com/userfiles/files/lulowematet.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/a401d4bb0a4f796e7dabe86e3b22ca4e/fojuritirujom.pdfIn PDF document text
    • https://ochronaskory.pl/pliki_user/File/peroninovuwabijuruvadis.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161385444670d1---64336613631.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613368970438b---88227327233.pdfIn PDF document text
    • http://krzeptowski.pl/file/70580060450.pdfIn PDF document text
    • http://www.kyousei-fukushi.or.jp/system/ckfinder/userfiles/files/87717106094.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/161364b22a2d3c---18333647422.pdfIn PDF document text
    • http://brucemayrockinstitute.com/assets/ckfinder/core/connector/php/uploads/files/90724824530.pdfIn PDF document text
    • http://abcbyspu.com/ckfinder/images_store/files/jirona.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/53fb3e0480977e4c792c72ccb4fa2aa1/wulanigolenejugosila.pdfIn PDF document text
    • https://apskarota.org/userfiles/file/27967689930.pdfIn PDF document text
    • http://zonazero.es/userfiles/file/61420884999.pdfIn PDF document text
    • http://elitsatodorova.com/uploadfiles/file/negiguvenodukolidunaxage.pdfIn PDF document text
    • https://tekmaker.com/upload/files/rurotizat.pdfIn PDF document text
    • http://aerotherminsulation.com/userfiles/file/fukukutikoxovapologode.pdfIn PDF document text
    • http://smartpaintingplus.com/userfiles/files/12462407167.pdfIn PDF document text
    • http://sakulchaiplace.com/Uploads/file/kenemopipademupovafomej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=poco+x3+compare+redmi+note+9sPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e88d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE88D 22072 bytes
SHA-256: f63a71494b7918707d5837c0701fb3d5831d34ecf28ed44db6db6c22b3a1d0d5
font_01_sfnt_off00012280.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12280 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013a97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A97 11072 bytes
SHA-256: 8d07796156a5e731a6d442d4f878534332275d39fa1973f9ce80f30df7895d68